The study looked at how well different types of willow trees can grow in tough conditions like salty soil or ash areas in Western Romania for energy use. They used special kinds of willow trees and checked things like how thick and tall the trees grew, as well as how many shoots each tree had. The researchers found that the willow trees could indeed grow in these tricky places, but they didn't make as much wood as they would on normal farm land. The results suggest that willow trees could be a possible source of energy from their biomass, even in challenging environments.